1. Field of the Invention
The present invention relates to a structure analysis processing method and program and a recording medium thereof, and more particularly to a structure analysis processing method and program and a recording medium which are employed in the structure analysis by a computer for computing the displacement and the stress by applying a pressure to a structure of various shapes, in which there is a minimum error produced by the computation method relying on the conventional VOXEL method.
2. Description of the Related Art
Conventionally, in the structure analysis problem for computing the displacement and the stress by applying a pressure to the curved surface of a structure, the structure was approximated by an aggregate of small rectangular parallelepipeds, each called a VOXEL, to calculate the displacement and the stress for its approximate model using the VOXEL method (finite element method, iteration method).
In the computation method relying on the VOXEL method, to attain the calculation precision, it was necessary to reduce an approximation error by making each size of VOXEL as small as possible.
In the structure analysis for computing the displacement and the stress by applying a pressure to the curved surface of the structure, the computation method relying on the VOXEL method involves making the computation by applying a pressure to the area (of indented surface) approximated by a stepped surface that is different from the area of the structure itself. Therefore, there is an error in the calculated displacement or stress, resulting in the analysis with poor precision to compute the untrue value.
If the VOXEL size is reduced more than needed to increase the analysis precision, there is a problem that the analysis process is inoperable because of insufficient machine resources such as the CPU time or memory, and the desired result cannot be obtained, whereby the minimum of VOXEL size was limited.
If the analysis precision was tried to increase within a range of usable machine resources, it was required that a full-time analysis engineer being well aware of the analysis method managed how to give the boundary conditions, and tried the analysis process under the changed conditions many times.
It is an object of the present invention to solve the above-mentioned problems intrinsic to the VOXEL method, and to provide a structure analysis processing method in which the reliability of analysis result is assured as an entire model by increasing the analysis precision in a VOXEL size analyzable with the machine resources actually employed in an analysis process, which is automated to enable the persons other than the analysis engineers to make the analysis with high precision.
Also, it is another object of the present invention to provide a structure analysis processing program that implements the structure analysis processing method.
Further, it is another object of the present invention to provide a recording medium that records the structure analysis processing program for implementing the structure analysis processing method.
A structure analysis processing method of the present invention for making the structure analysis of a modeled analysis object to which a pressure is applied, using the VOXEL method. The method comprises calculating a pressure Vp to be applied to a VOXEL model for the analysis object in accordance with an expression
Vp=Fpxc3x97Cs/Vs
where the pressure applied on the analysis object is Fp, an actual area of the analysis object to apply the pressure is Cs, and the area in the VOXEL model corresponding to the actual area for applying the pressure is Vs, and making the structure analysis using the VOXEL method with the calculated pressure Vp as the pressure applied to the VOXEL model.
Also, the structure analysis processing program of the present invention is executed on the computer to implement the structure analysis processing method.
Further, the structure analysis processing program recording medium of the present invention is a computer readable recording medium for recording the structure analysis processing program.
Also, another structure analysis processing method of the present invention for making the structure analysis of a modeled analysis object to which a pressure is applied, using the VOXEL method. The method comprises calculating a pressure to be applied to a VOXEL model of the analysis object, calculating a structure analysis value of interest and a reaction force at a point of fulcrum by the structure analysis computation using the VOXEL method, calculating a corrected pressure which corrects the pressure to be applied to the VOXEL model for an error between a theoretically correct reaction force corresponding to a load on the analysis object and a total of the calculated reaction forces at the points of fulcrum, and performing the structure analysis computation again, using the VOXEL method, based on the corrected pressure.
Also, another structure analysis processing program of the present invention is executed on the computer to implement the structure analysis processing method.
Further, another structure analysis processing program recording medium of the present invention is a computer readable recording medium for recording the structure analysis processing program.
Further, another structure analysis processing method of the present invention for making the structure analysis of a modeled analysis object to which a pressure is applied, using the VOXEL method. The method comprises calculating a pressure Vp to be applied to a VOXEL model for the analysis object in accordance with an expression
Vp=Fpxc3x97Cs/Vs
where the pressure Vp is as an initial value of the pressure to be applied in the structure analysis computation, the pressure applied on the analysis object is Fp, an actual area of the analysis object to apply the pressure is Cs, and the area in the VOXEL model corresponding to the actual area for applying the pressure is Vs, calculating a structure analysis value of interest and a reaction force at a point of fulcrum by the structure analysis computation using the VOXEL method, calculating a corrected pressure which corrects the pressure to be applied to the VOXEL model for an error between a theoretically correct reaction force corresponding to a load on the analysis object and a total of the calculated reaction forces at the points of fulcrum, and performing the structure analysis computation again, using the VOXEL method, based on the corrected pressure.
Also, another structure analysis processing program of the present invention is executed on the computer to implement the structure analysis processing method.
Further, another structure analysis processing program recording medium of the present invention is a computer readable recording medium for recording the structure analysis processing program.